Methodology of removing misplaced encapsulant for attachment of heat sinks in a chip on board package

A method for preventing an encapsulant material from adhering to a surface of a chip scale semiconductor package comprising:

• applying a layer of material as a mask to a portion of said surface of said chip scale semiconductor package;
• applying an encapsulant material to the remaining portion of said surface of said chip scale semiconductor package;
• curing said encapsulant material;
• removing said layer of material from said surface of said chip scale semiconductor package said removing including peeling said layer from said surface of said semiconductor die;
• providing a substrate;
• bonding said chip scale package to said substrate;
• providing a heat sink having at least one surface;
• and
• securing said heat sink to said surface of said chip scale semiconductor package.

A method for preventing glob top material from adhering to a surface of a semiconductor die comprising:

• applying a first layer of material to said surface of said semiconductor die;
• applying a second layer of material as a mask to a portion of said surface of said first layer of material;
• applying an encapsulant material to the remaining portion of said surface of said semiconductor die;
• curing said glob top material
• removing said layer of material from said surface of said semiconductor die, said removing including peeling said layer from said surface of said semiconductor die;
• providing a heat sink having at least one surface;
• and
• securing said heat sink to a surface of said second layer of material.

A method for preventing glob top material from adhering to a surface of a semiconductor die comprising:

• applying a layer of material as a mask to a portion of said surface of said semiconductor die;
• applying glob top material to the remaining portion of said surface of said semiconductor die;
• curing said glob top material;
• removing said layer of material from said surface of said semiconductor die, said removing including peeling said layer from said surface of said semiconductor die;
• providing a heat sink having at least one surface;
• and
• securing said heat sink to said surface of said semiconductor die.

A method for fabricating a Chip On Board semiconductor device with a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, and edges therebetween;
• providing a substrate;
• providing a thermally conductive heat sink member;
• attaching the first side of said semiconductor die to said substrate;
• covering at least a portion of the second side of said semiconductor die with a material having an exposed surface;
• applying a material to encapsulate said edges of said semiconductor die;
• maintaining said exposed surface of said material covering at least a portion of the second side of said semiconductor die substantially unencapsulated;
• curing said material to encapsulate said edges of said semiconductor die;
• removing said material having an exposed surface covering at least a portion of the second side of said semiconductor die ,said removing including peeling said material from said surface of said semiconductor die;
• and
• attaching said heat sink member to the second side of said semiconductor die.

A method for preventing glob top material from adhering to a surface of a semiconductor die comprising:

• applying a layer of gel elastomer material as a mask to a portion of said surface of said semiconductor die;
• applying glob top material to the remaining portion of said surface of said semiconductor die;
• curing said glob top material;
• peeling said gel elastomer material from said surface of said semiconductor die;
• and
• attaching a surface of a heat sink to said surface of said semiconductor die.

A method for fabricating a Chip On Board semiconductor device with a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, edges therebetween, and electrical terminals;
• providing a substrate having electrical connections;
• providing a thermally conductive heat sink member;
• attaching the first side of said semiconductor die to said substrate;
• connecting said electrical terminals of said semiconductor die to said electrical connections of said substrate;
• covering at least a portion of the second side of said semiconductor die with a compliant protective layer having an exposed surface;
• applying a material to encapsulate said electrical terminals and die edges;
• maintaining said exposed surface of said protective layer substantially unencapsulated by said material;
• curing said material;
• removing said protective layer, said removing including peeling said protective layer;
• and
• attaching said heat sink member to the second side of said semiconductor die.

A method for fabricating a semiconductor device assembly having a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, and edges therebetween;
• providing a substrate;
• providing a thermally conductive heat sink member;
• attaching the first side of said semiconductor die to said substrate;
• covering at least a portion of the second side of said semiconductor die with a material having an exposed surface;
• applying a material to encapsulate said edges of said semiconductor die;
• maintaining said exposed surface of said material covering at least a portion of the second side of said semiconductor die substantially unencapsulated;
• curing said material to encapsulate said edges of said semiconductor die;
• removing said material having an exposed surface covering at least a portion of the second side of said semiconductor die, said removing said material including peeling said material away from the second surface of said semiconductor die;
• and
• attaching said heat sink member to the second side of said semiconductor die.